Fan Casting Ice Age 2: The Meltdown (2007)

Manny, Sid, and Diego are currently living in a large valley surrounded by an enormously high ice wall on all sides. However, the trio subsequently discovers that the ice wall is actually a dam that is barely holding a massive reservoir that could flood the valley to nearly a mile underwater if it fails. A vulture tells them that there is a boat at the other end of the valley that may save them all, but they only have three days to reach it or die. Shortly after, a huge chunk of ice breaks off from the top of the dam, initiating their immediate evacuation.